CN110784233A - Physical layer scrambling code sequence recovery method in DVB-S2 standard - Google Patents
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M13/00—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
- H03M13/03—Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words
- H03M13/05—Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits
- H03M13/11—Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits using multiple parity bits
- H03M13/1102—Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
- H03M13/1148—Structural properties of the code parity-check or generator matrix
- H03M13/1154—Low-density parity-check convolutional codes [LDPC-CC]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/438—Interfacing the downstream path of the transmission network originating from a server, e.g. retrieving encoded video stream packets from an IP network
- H04N21/4382—Demodulation or channel decoding, e.g. QPSK demodulation
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- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
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Abstract
The invention has proposed a physical layer scrambling code sequence recovery method in DVB-S2 standard, utilize the relation of check matrix and code word of the parity check code of the low density, regard check sum minimum as the judgement criterion, this method traverses all possible scrambling code sequences, after descrambling under each sequence, constellation map inverse mapping, calculate the check sum of LDPC code word, the scrambling code sequence that the minimum check sum corresponds is the sequence used for scrambling; the method is irrelevant to the information source characteristics, can realize single-frame scrambling code recovery, and is particularly suitable for application and a burst synchronous communication system.
Description
Technical Field
The invention relates to the field of scrambling code analysis, in particular to a method for recovering a physical layer scrambling code sequence in a DVB-S2 standard.
Background
The Second Generation Digital Video Broadcasting (DVB-S2) standard is one of the most successful Digital communication standards and is therefore widely used in various communication systems. In the DVB-S2 standard, in addition to bit scrambling the source, physical layer scrambling is performed on the symbols to reduce mutual interference between different services and different beams, and the scrambling codes can also be used as address codes for multiple access communications. However, there is no clear instruction in the standard to transmit the physical layer scrambling code sequence parameter, and in the application of adaptive communication, etc., the receiving party does not know the scrambling code sequence parameter, and at this time, the receiving party needs to recover the scrambling code sequence first and then descramble.
In the aspect of recovering the DVB-S2 physical layer scrambling code sequence, the main methods adopted currently are as follows: firstly, descrambling is carried out on the information source, and then the scrambling sequence is recovered bit by bit through multi-frame accumulation by utilizing the imbalance of 0 and 1 of the information source. However, this approach has significant problems:
firstly, multi-frame accumulation is needed, the needed accumulation times are exponentially increased along with the reduction of the unbalance degree of the information sources 0 and 1, and if the unbalance of the information sources 0 and 1 is very small due to the self characteristics of the information sources or the adoption of information source coding, the needed accumulation times are too large to enable the algorithm to be not practically applied;
secondly, in a burst communication system, the receiving party receives data frames very limitedly and does not necessarily have the condition of multi-frame accumulation;
thirdly, when the error rate is large, the existence of error bits can destroy the imbalance of 0 and 1 of the information source, so that the algorithm is invalid.
Therefore, no better means for recovering the physical layer scrambling sequence in the DVB-S2 standard is available at present, which breaks through the above method.
Disclosure of Invention
The invention has proposed a DVB-S2 standard physical layer scramble sequence recovery method, utilize Check matrix and relation of the code word of the Low Density Parity Check code (LDPC), regard Check sum minimum as the judgement criterion, this method traverses all possible scramble sequences, descramble under each sequence, after constellation map inverse mapping, calculate Check sum of LDPC code word, the scramble sequence that the minimum Check sum corresponds is the sequence used for scrambling; the method is irrelevant to the information source characteristics, can realize single-frame scrambling code recovery, and is particularly suitable for application and a burst synchronous communication system.
In the art, the principle of DVB-S2 physical layer scrambling is as follows:
the general transmission process for the DVB-S2 communication link is: after bit scrambling, firstly carrying out binary BCH coding and then carrying out LDPC coding on an information source; carrying out constellation mapping on the coded bit stream according to the selected modulation mode to generate a symbol sequence corresponding to the modulation mode; after the constellation map is mapped, carrying out physical layer scrambling; and the symbol after the physical layer scrambling is subjected to baseband shaping and quadrature modulation to generate an intermediate frequency modulation signal for output. According to different modulation modes and channel conditions, links such as symbol interleaving and pilot insertion may exist.
The physical layer scrambling process in the DVB-S2 communication link is as follows:
construction of pseudorandom sequences x and y
x(0)=1,x(1)=x(2)=…=x(17)=0 (1)
y(0)=y(1)=y(2)=…=y(17)=1 (2)
(a) Construction of a pseudorandom sequence z
n
Where mod (i + d, 2)
18-1) represents i + d pair 2
18-1 modulo remainder; d is an offset.
(b) Construction of scrambling sequence R
d
R
d(i)=2z
d(mod(i+131072,2
18-1))+z
d(i),i=0,1,...,2
18-2 (6)
(c) Physical layer scrambling
S
c(i)=S(i)exp(jR
d(i)π/2),i=0,1,…,L-1 (7)
Wherein S (i), S
c(i) Respectively before and after scrambling, and L is the frame length taking the symbol as a unit;
therefore, according to the above mentioned physical layer scrambling process, the physical layer scrambling code sequence recovered in the present invention is the recovery sequence R
dProvided that R is obtained
dThe scrambled sequence can be descrambled,
S(i)=S
c(i)exp(-jR
d(i)π/2),i=0,1,…,L-1 (8)
and the reconstructed R is known from the formulas (5) and (6)
dThe key to estimating the offset d.
The inner code of DVB-S2 adopts LDPC coding, and the LDPC coding parameters can be obtained according to the physical frame header of DVB-S2 frame; in addition, modulation mode information can be obtained through a physical frame head which does not participate in physical layer scrambling, and LDPC parameters are set, the modulation mode is known, and operations such as carrier removal, timing extraction and the like are finished.
LDPC coding is essentially a linear block code, assuming a message block length of k and a codeword length of n, a message block m ═ m
1,m
2,…,m
k]And corresponding codeword c ═ c
1,c
2,…,c
n]There is a relationship that,
c=mG (9)
where G is a k n dimensional matrix, referred to as a generator matrix. There is an (n-k) × n dimensional matrix H, satisfying,
GH
T=0
k×(n-k)(10)
called H as the check matrix corresponding to G, where 0
k×(n-k)Represents a k × (n-k) dimensional all-zero matrix. Can be obtained from the formulae (9) and (10),
cH
T=mGH
T=0
1×(n-k)(11)
wherein 0
1×(n-k)The matrix is a 1 x (n-k) all-zero matrix, namely the code word is multiplied by the corresponding check matrix transpose, and the n-k dimensional all-zero row vector is obtained. The generation method of the check matrix H when different n and k values are given in the DVB-S2 standard, so H can be obtained as long as n and k are known, and the values of n and k can be determined according to the information in the physical frame header.
It is assumed that the scrambling sequence R is generated with a certain offset l
lDescrambling is carried out according to the formula (8) to obtain a sequence S
l,
S
l(i)=S
c(i)exp(-jR
l(i)π/2),i=0,1,…,L-1 (12)
Then according to the modulation mode to S
lAn n-dimensional row vector c can be obtained by inverse mapping of the constellation diagram
l. Defining check word ch
lAnd the checksum chs
lIn order to realize the purpose,
ch
l=c
lH
T,l=0,1,...,2
18-2 (13)
thus, it can be seen that: if there is no error code, when l is d, c
l=c
dIs an LDPC code word, the checksum chs thereof
l=chs
d0; when there is error code, chs when l ═ d
l=chs
dThe minimum value should be taken. It is thus obtained that the estimated expression of the offset d is,
wherein
The estimated value of d is represented by,
indicating that chs is taken
lThe minimum value of l. To obtain
Then obtaining the compound according to the formula (5)
Then, the physical layer scrambling code sequence is recovered according to the formula (6)
In summary, with known coding parameters n, k, from the received symbol sequence S
cRecovering scrambling code sequence in middle
The steps are as follows:
1) constructing pseudorandom sequences x and y
x(0)=1,x(1)=x(2)=…=x(17)=0
y(0)=y(1)=y(2)=…=y(17)=1
2) Obtaining a check matrix H according to n and k;
3) taking l as 0;
4) calculating z
lAnd R
l
R
l(i)=2z
l(mod(i+131072,2
18-1))+z
l(i),i=0,1,...,L-1
5) By means of R
lFor the symbol sequence S
cThe descrambling is carried out in such a manner that,
S
l(i)=S
c(i)exp(-jR
l(i)π/2),i=0,1,…,L-1
6) according to modulation mode pair S
lInverse mapping of constellation diagram to obtain c
l;
7) The check word and the check sum are calculated,
8) if l < 2
18-2, take l ═ l +1, go to 4), otherwise go to 9);
9) the amount of the offset is estimated and,
The invention has the following beneficial effects:
the invention uses the relation between the check matrix of the low-density parity check code and the code word to traverse all possible sequences, and realizes the recovery of the physical layer scrambling code sequence by the check sum minimum judgment criterion; meanwhile, the invention is irrelevant to the information source characteristics, can realize single frame recovery without multi-frame accumulation, has stronger adaptability and is particularly suitable for the application environment of burst communication; in addition, due to the sparsity of the LDPC check matrix, the error code resistance is also strong.
Drawings
Fig. 1 is a flow chart of physical layer scrambling code sequence recovery of the present invention.
Fig. 2 is a schematic diagram of a change of the checksum with the offset value l in the embodiment.
Detailed Description
The invention provides a physical layer scrambling code sequence recovery method in DVB-S2 standard, which uses the relation between the check matrix of low density parity check code and code word, and uses the minimum check sum as the judgment criterion, the method traverses all possible scrambling code sequences, after descrambling under each sequence and inverse mapping of constellation diagram, calculates the check sum of LDPC code word, the scrambling code sequence corresponding to the minimum check sum is the scrambling sequence, namely the recovery sequence R
dProvided that R is obtained
dThe scrambled sequence can be descrambled and the recovery flow is shown in fig. 1.
An example of recovery according to the above-described flow chart is as follows:
in a DVB-S2 communication link, a modulation mode is QPSK, a frame length L is 8100, a corresponding LDPC coding parameter is n 16200, an offset d is 11 when k is 7200 physical layer scrambling code sequences, and a signal-to-noise ratio is 0 dB. The process of reconstructing the physical layer scrambling code sequence by the receiving end is as follows:
a) constructing pseudo-random sequences x and y;
b) obtaining a check matrix H according to the conditions that n is 16200 and k is 7200;
c) take l as 0,1, 2
18-2 and at each value of l, calculating R
lDescrambled to obtain S
lAccording to the modulation mode, inverse mapping of the constellation diagram is carried out to obtain c
lAnd then the checksum chs is obtained
l,chs
lThe variation along with l is shown in FIG. 2, and l is only 0-21 for easy observation;
It can be seen from the above application example that the physical layer scrambling code sequence is correctly recovered according to the method of the present invention, and the method has strong error code resistance.
Claims (5)
1. A method for recovering a physical layer scrambling code sequence in DVB-S2 standard is characterized in that: by using the relation between the check matrix of the low-density parity check code and the code word and taking the minimum check sum as a judgment criterion, traversing all possible scrambling code sequences, calculating the check sum of the LDPC code words after performing inverse mapping on a constellation diagram under each scrambling code sequence, and obtaining the scrambling code sequence R corresponding to the check sum
dThen recovering the scrambling code sequence R
d。
2. Method for recovering the physical layer scrambling code sequence in the DVB-S2 standard according to claim 1, wherein the received symbol sequence S is decoded when the coding parameters n, k are known
cRecovering scrambling code sequence in middle
The method comprises the following specific steps:
(1) constructing pseudorandom sequences x and y
(2) Obtaining a check matrix H according to the coding parameters n and k; wherein n is the code word length, and k is the message packet length;
(3) one set offset l is taken, the set offset l is made to be 0, and the corresponding set scrambling code sequence R is generated
lSetting the scrambling code sequence R
lDescrambling is carried out according to the following formula to obtain a sequence S
l:
S
l(i)=S
c(i)exp(-jR
l(i)π/2)
Wherein: i is 0,1, …, L-1, L is the frame length in symbol;
(4) the pseudo-random sequence z is calculated as follows
lAnd setting scrambling code sequence R
l:
R
l(i)=2z
l(mod(i+131072,2
18-1))+z
l(i),i=0,1,...,L-1;
(5) Using said set scrambling sequence R
lFor the symbol sequence S
cDescrambling was performed as follows:
S
l(i)=S
c(i)exp(-jR
l(i)π/2),i=0,1,…,L-1;
(6) according to modulation mode pair S
lInverse mapping is carried out on the constellation diagram to obtain an n-dimensional row vector c
l;
(7) Calculating check word ch
lAnd the checksum chs
l:
ch
l=c
lH
T,
(8) If l < 2
18-2, taking l ═ l +1, go to step (4), otherwise go to 9);
(9) estimating an offset:
wherein
An estimate value representing the amount of offset,
indicating that chs is taken
lThe minimum value of l;
3. A method for recovering a physical layer scrambling sequence in the DVB-S2 standard according to claim 2, wherein: according to the message packet length k and the code word length n, obtaining the message packet m ═ m
1,m
2,…,m
k]And corresponding codeword c ═ c
1,c
2,…,c
n]The relationship between:
c=mG;
g is a k multiplied by n dimensional matrix called a generator matrix;
there is an (n-k) × n dimensional matrix H satisfying:
GH
T=0
k×(n-k);
the matrices H and G are corresponding check matrices, where 0
k×(n-k)Represents a k × (n-k) dimensional all-zero matrix.
4. A method for recovering a physical layer scrambling sequence in the DVB-S2 standard according to claim 3, wherein: according to the DVB-S2 standard, the generation method of the check matrix H when different values of n and k are obtained can be realized, so that H can be obtained according to n and k, and the values of n and k are determined according to the information in the physical frame header.
5. A method for recovering the scrambling code sequence of the physical layer in DVB-S2 standard according to claim 2, wherein the check word ch is calculated in step (7)
lAnd the checksum chs
lAnd then, taking the minimum checksum as a judgment criterion:
if there is no error code, when l ═ d,c
l=c
dIs an LDPC code word, the checksum chs thereof
l=chs
d=0;
When there is error code, chs when l ═ d
l=chs
dThe minimum value should be taken.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112804583A (en) * | 2020-12-30 | 2021-05-14 | 中科院计算技术研究所南京移动通信与计算创新研究院 | Physical layer signaling code PLSC demodulation method based on DVB-S2 standard |
CN112821895A (en) * | 2021-04-16 | 2021-05-18 | 成都戎星科技有限公司 | Code identification method for realizing high error rate of signal |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007050808A2 (en) * | 2005-10-27 | 2007-05-03 | Qualcomm Incorporated | A method and apparatus for cell-specific scrambling in wireless communication system |
CN101018224A (en) * | 2006-12-15 | 2007-08-15 | 北京创毅视讯科技有限公司 | Information transmission and receiving method and end of the mobile digital multimedia broadcast physical layer signaling |
CN101083500A (en) * | 2006-02-08 | 2007-12-05 | 直视集团公司 | Blind identification of advanced modulation and coding modes |
CN101562456A (en) * | 2009-06-03 | 2009-10-21 | 华北电力大学(保定) | Code assisting frame synchronizing method based on soft decoding information of low-density parity check codes |
US20140313994A1 (en) * | 2011-09-01 | 2014-10-23 | China Academy Of Telecommunications Technology | Method and device for transmitting downlink control information |
CN106330800A (en) * | 2016-08-22 | 2017-01-11 | 杭州国芯科技股份有限公司 | Fast search method for physical layer scrambling parameter based on pilot symbol |
CN106464270A (en) * | 2014-05-21 | 2017-02-22 | 三星电子株式会社 | Transmitting apparatus and interleaving method thereof |
JP2019126017A (en) * | 2018-01-18 | 2019-07-25 | ソニー株式会社 | Transmission method and reception device |
-
2019
- 2019-10-31 CN CN201911055758.4A patent/CN110784233B/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007050808A2 (en) * | 2005-10-27 | 2007-05-03 | Qualcomm Incorporated | A method and apparatus for cell-specific scrambling in wireless communication system |
CN101083500A (en) * | 2006-02-08 | 2007-12-05 | 直视集团公司 | Blind identification of advanced modulation and coding modes |
CN101018224A (en) * | 2006-12-15 | 2007-08-15 | 北京创毅视讯科技有限公司 | Information transmission and receiving method and end of the mobile digital multimedia broadcast physical layer signaling |
CN101562456A (en) * | 2009-06-03 | 2009-10-21 | 华北电力大学(保定) | Code assisting frame synchronizing method based on soft decoding information of low-density parity check codes |
US20140313994A1 (en) * | 2011-09-01 | 2014-10-23 | China Academy Of Telecommunications Technology | Method and device for transmitting downlink control information |
CN106464270A (en) * | 2014-05-21 | 2017-02-22 | 三星电子株式会社 | Transmitting apparatus and interleaving method thereof |
CN106330800A (en) * | 2016-08-22 | 2017-01-11 | 杭州国芯科技股份有限公司 | Fast search method for physical layer scrambling parameter based on pilot symbol |
JP2019126017A (en) * | 2018-01-18 | 2019-07-25 | ソニー株式会社 | Transmission method and reception device |
Non-Patent Citations (2)
Title |
---|
HAO WU等: "Estimation of Physical Layer Scrambling Code", 《ETRI JOURNAL》 * |
张玉龙等: "一种改进的DVB-S2接收机帧同步方案", 《计算机工程》 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112804583A (en) * | 2020-12-30 | 2021-05-14 | 中科院计算技术研究所南京移动通信与计算创新研究院 | Physical layer signaling code PLSC demodulation method based on DVB-S2 standard |
CN112804583B (en) * | 2020-12-30 | 2022-09-13 | 南京中科晶上通信技术有限公司 | Physical layer signaling code PLSC demodulation method based on DVB-S2 standard |
CN112821895A (en) * | 2021-04-16 | 2021-05-18 | 成都戎星科技有限公司 | Code identification method for realizing high error rate of signal |
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